Results 1 to 9 of 9

Trans shifts to higher gear between 35-50 at half throttle

This is a discussion on Trans shifts to higher gear between 35-50 at half throttle within the Automatic Transmission forums, part of the Drivetrain category; When cruising between about 35-50mph if i give it about half throttle the rpms go up and the transmission seems ...

  1. #1
    Junior Member
    Join Date
    Dec 2010
    Location
    Louisiana
    Posts
    50
    02 WS6 Stock

    Trans shifts to higher gear between 35-50 at half throttle

    When cruising between about 35-50mph if i give it about half throttle the rpms go up and the transmission seems to shift into a higher gear and it bogs down.

    I don't know if it's related but it shifts hard from 1st to 2nd too unless you're taking it real easy on the throttle.

    Other than that, the transmission shifts great.

    I just purchased the car, the owner before me said she had the transmission rebuilt within the last year. It's completely stock except for an SLP lid.


    One more thing, I know this might be a stupid question but.. from a dead stop it shifts 4 times, wouldn't that make it a 5-speed?
    Last edited by elwood; 01-16-2011 at 05:08 AM.

  2. #2
    Moderator Cutlass's Avatar
    Join Date
    Apr 2008
    Location
    Madison, WI
    Posts
    6,996

    1999 Formula WS6 M6-sold
    2001 Silverado Z71

    The "fifth" shift is actually the torque converter clutch lock-up. Its not an actual gear, it just eliminates the slip in the torque converter.

  3. #3
    Junior Member
    Join Date
    Dec 2010
    Location
    Louisiana
    Posts
    50
    02 WS6 Stock

    Quote Originally Posted by Cutlass View Post
    The "fifth" shift is actually the torque converter clutch lock-up. Its not an actual gear, it just eliminates the slip in the torque converter.
    Ok, kinda figured that, thanks. Any advice on the shifting problem?

  4. #4
    Moderator Cutlass's Avatar
    Join Date
    Apr 2008
    Location
    Madison, WI
    Posts
    6,996

    1999 Formula WS6 M6-sold
    2001 Silverado Z71

    Not really sure. the hard 1-2 shift could be a shift kit that the previous owner installed or programmed into the computer.
    Can you describe the other problem a little more? So you're cruising at 50mph, you push the pedal down about half way, the rpms jump up (how much??) but you think its up shifting??

  5. #5
    Junior Member
    Join Date
    Dec 2010
    Location
    Louisiana
    Posts
    50
    02 WS6 Stock

    Quote Originally Posted by Cutlass View Post
    Not really sure. the hard 1-2 shift could be a shift kit that the previous owner installed or programmed into the computer.
    Can you describe the other problem a little more? So you're cruising at 50mph, you push the pedal down about half way, the rpms jump up (how much??) but you think its up shifting??
    I'm pretty sure it doesn't have a stall higher than factory if that's what you're asking about.

    The RPM's just go up as i give it more gas (300-500 increase maybe) then the transmission up shifts and it bogs down because of the higher gear. Like the shift times are off. I guess it's hard for me to explain.

    I'll try to get a video of it tomorrow or Monday when I'm off.

    P.S. I will soon have an OBD-II to iPhone cable so i can really see what's going on with the computer.

  6. #6
    Moderator Cutlass's Avatar
    Join Date
    Apr 2008
    Location
    Madison, WI
    Posts
    6,996

    1999 Formula WS6 M6-sold
    2001 Silverado Z71

    yeah a video would be helpful. That OBDII iPhone cable sounds neat!

  7. #7
    Junior Member
    Join Date
    Dec 2010
    Location
    Louisiana
    Posts
    50
    02 WS6 Stock

    Ok, I took some video which I can't post right now because I'm at work. It doesn't show much anyway. The road noise is louder than the stock exhaust so you can't tell much.

    Anyhow, I'm pretty sure the "shift" I feel is the torque converter "unlocking". The RPMs don't really move when it "shifts" except in the correlation with the acceleration.

    I'm pretty sure it's an issue with the computer tuning for the transmission.

    I just need to figure out if I spend $100 on the OBD-II to iPhone adapter if it's going to give me the information I'm looking for.

    On a regular scanner/logger does it show information about the transmission parameters?
    Last edited by elwood; 01-16-2011 at 04:51 PM.

  8. #8
    Moderator Cutlass's Avatar
    Join Date
    Apr 2008
    Location
    Madison, WI
    Posts
    6,996

    1999 Formula WS6 M6-sold
    2001 Silverado Z71

    Quote Originally Posted by elwood View Post
    Ok, I took some video which I can't post right now because I'm at work. It doesn't show much anyway. The road noise is louder than the stock exhaust so you can't tell much.

    Anyhow, I'm pretty sure the "shift" I feel is the torque converter "unlocking". The RPMs don't really move when it "shifts" except in the correlation with the acceleration.

    I'm pretty sure it's an issue with the computer tuning for the transmission.

    I just need to figure out if I spend $100 on the OBD-II to iPhone adapter if it's going to give me the information I'm looking for.

    On a regular scanner/logger does it show information about the transmission parameters?
    Some do, some don't. You need to look specifically for one that says it shows domestic transmission data

  9. #9
    Senior Member JayTA98's Avatar
    Join Date
    Dec 2007
    Location
    Orlando, FL
    Posts
    3,351

    Mean Black
    1998 Trans Am

    If is a tuning issue you are better off taking it to a tuner and save the $100 dollars for that. Some tuners will charge to check your PCM but then you can be sure if it is a A4 tunning issue. I will PM Frost and ask him how much he will charge you for tuning the tranny only. His mail tune service is awesome.

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Half throttle+ causes violent throttle response
    By AKIRA in forum General Help
    Replies: 5
    Last Post: 08-14-2013, 09:26 AM
  2. Replies: 16
    Last Post: 02-24-2011, 11:17 AM
  3. Slight hesitation at half throttle acceleration
    By 5abivt in forum General Help
    Replies: 3
    Last Post: 06-13-2009, 10:53 PM
  4. Ported Throttle Body and higher idle??
    By Midnight02 in forum External Engine
    Replies: 4
    Last Post: 03-24-2007, 12:21 AM
  5. 3rd and a half gear???
    By Black Dragon in forum Automatic Transmission
    Replies: 7
    Last Post: 12-25-2006, 09:18 AM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •